Vernier dial indicating mechanism for production machines



July 10, 1956 VERNIER DIAL INDICATING MECHANISM FOR PRODUCTION MACHINES FIG.

E. J- BOURGUIGNON Filed March 24, 1954 INVENTOR. Emil Joseph Bourguignon ATTORNEYS United States Patent VERNIER DIAL INDICATING MECHANISM FOR PRODUCTION MACHINES Emil Joseph Bourguignon, Farmingdale, N. Y.

Application March 24, 1954, Serial No. 418,383

14 Claims. (Cl. 116-115) My invention relates to improvements in vernier dial indicating mechanisms for production machines, such as lathes, turret lathes, millers, grinders, jig borers and other machines provided with means for adjusting the amount of material to be removed from a workpiece.

Such machines presently include a hand wheel for adjusting the position of a cross slide or equivalent means and a dial operated by the handle or hand wheel with respect to a zero index on the carriage or other fixed part of the mechanism. The regular dial is conventionally divided into closely spaced divisions representing thousandths of an inch. This standard arrangement has been found to be entirely unsatisfactory because of the closely spaced graduations and the difficulty involved in moving the cross slide a portion of a graduation. Furthermore, the graduations are so close together that it is diflicult to see them without bending over and without considerable eyestrain, and it is difiicult to adjust for close tolerances.

Some attempts have been made to overcome the foregoing conditions by incorporating a vernier dial arrangement along with the regular dial but such proposed constructions have never been adopted, apparently because they were entirely too expensive, too complicated or did not prove sufliciently accurate in service. In some cases it is possible that the gear mechanisms used to operate the vernier arrangement could not be made in such a way to eliminate play or overcome the result of wear.

The primary object, therefore, of the present invention is to provide an improved vernier dial indicating mechanism which will increase the effectiveness and accuracy of machining operations and permit the holding of close tolerances in such operations.

A further object of the invention is to provide an improved vernier dial arrangement for production machines which can readily be maintained in perfect operating condition.

Another object of the invention is to provide a vernier dial construction for production machines which is adapted to eliminate eyestrain and the other disadvantages referred to above.

According to my invention I have modified the standard dial arrangement, for example, that of a cross slide, by including a vernier dial mounted directly in back of the standard dial and rotatable on the cross feed shaft to which the standard dial is fixed. In addition, in modifying existing dial structures at least, I preferably provide a support plate between the vernier dial and the regular fixed mounting normally carrying the zero index for the standard dial, this support plate being fixed to the mounting and carrying means for pivoting parts of the gear mechanism to be driven by the feed screw shaft for operating the vernier dial. In this arrangement the vernier dial carries widely spaced graduations, each representing one thousandth of an inch so that they are easily seen by the operator who in turn can readily adjust the cross slide one-half, one-fourth or some other simple fraction of a thousandth of an inch. In newconstrucice tions the means for pivoting parts of the gear mechanism may be carried in or on the face of the fixed mounting or carriage, or the support plate may be used.

In a preferred construction the support plate, or the carriage, carries an adjustable shaft for certain gears for driving the vernier dial, this shaft being movable bodily toward and away from the axis of the cross slide screw shaft for maintaining the gears in closely meshing relationship, thereby avoiding any play or back lash between the cross slide shaft and the vernier dial. In this construction the movable shaft carried by the support plate or carriage is parallel to the cross slide shaft and preferably mounted eccentrically in a rotatable disc set in the plate, or carriage, the disc being provided with means for elfecting its rotation for the purpose of moving the shaft toward and away from the cross slide shaft. This mechanism has the further advantage that the gears may be more readily assembled by rotating the gear supporting shaft away from the cross slide shaft until the gears are assembled in place and then moving the gear supporting shaft toward the cross slide shaft.

The improved vernier dial indicating mechanism includes other features and advantages which are described more in detail hereinafter in connection with the accompanying drawings, in which:

vFig. 1 is a broken side elevational view partly in section of a vernier dial indicating mechanism according to the invention illustrated in connection with certain standard elements of a cross slide of a turret lathe;

Fig. 2 is a broken horizontal sectional view taken on the line 22 of Fig. 1;

Fig. 3 is a fragmentary view on an enlarged scale looking down on the scales of the dial arrangement shown in Fig. 1, taken from the position of the line 3-3 in Fig. 1;

Fig. 4 is a broken view partly in section taken on the line 44 of Fig. 2 and drawn to a smaller scale, and

Fig. 5 is a broken sectional view taken on the line 55 of Fig. 2.

Fig. 1 shows certain of the conventional elements of a cross slide mechanism for a turret lathe which includes the usual carriage mounting 10 for a cross feed screw shaft 12 which normally operates in the nut of the cross slide, not shown. The regular mechanism also includes a handle 14 mounted on and keyed to the projecting end of the shaft 12 and a dial 16 keyed to the shaft 12 and provided with a cylindrical scale 18 graduated in thousandths of an inch.

According to the embodiment of the present invention as illustrated in the drawings, the improved vernier dial construction comprises a support plate 20 and a vernier dial 22 arranged as shown between the dial 18 and the carriage 10, both concentric to the shaft 12. The support plate 20 has a bore somewhat larger than the diameter of the shaft 12 and is fixed to the end of the carriage 10 by means of recessed screws 24, two of which are shown in Fig. 4. The vernier dial 22 includes a hub 26 extending forwardly in a cylindrical recess in the dial 16 and having a larger bore than the diameter of the shaft 12. The hub 26 carries a disc 28 extending radially along the back face of the dial 16 and provided with a cylindrical flange 30 which extends back to the support plate 20. The vernier dial 22 is freely rotatable with respect to the dial 16, the shaft 12 and the support plate 20.

The means for rotating the vernier dial 22 from the shaft 12 comprises a system of gears including a gear 32 of relatively large diameter keyed to the shaft 12 by a key 34, a relatively small gear 36 meshing with the gear 32 and rotatable on a stub shaft 38 carried by the support plate 20, a relatively large diameter gear 40, the same diameter as the gear 32, fixed to the hub 42 of the gear 36, and a relatively small gear 44, the same size as the gear 36 and rotatable on the shaft '12 and meshing with the gear 40. The gear 44 is provided with a forwardly projecting hub or sleeve section 46 which fits in and is fixed to the hub 26 of the Vernier dial 22 so that rotation of the shaft 12 operates the various gears referred to and rotates the Vernier dial 22 in the same direction and at a rate faster than that of the dial 16, which rate is determined by the ratio of the sizes of the gears 32 and 36. The hub 26 may be fixed to the hub or sleeve 46, and the gear 40 fixed to the hub 42 y press fitting, internal welding or other means.

The stub shaft 33 is mounted so that it is adjustable toward and away from the shaft 12 for the purpose of securing a firm fit without play between the gears 36 and 40 and the respective gears 32 and 44. The construction for effecting this adjustment and for eliminating any play in the gears is shown in Figs. 2, 4 and from which it will be noted that the shaft 38 is set eccentrically with respect to and carried by a rotatable disc 48 mounted in a cylindrical bore in the support plate 20, the front of the disc 48 being flush with the front of the plate 20 and its back resting against the face of the mounting 10. The disc 43 and the stub shaft are preferably integral, as shown. A pin 50 with chisel-shaped ends extends through the disc 48 and its ends are operable in recesses 52 on opposite sides of the disc 48 in the back half of the plate 20. The ends of the pin 50 extend into the respective recesses 52, which are sufficiently wide to permit swinging of the pin for rotating the disc 48 in the plate 20 on an axis at right angles to the plate. The means for effecting this rotation and for setting the shaft 38 and the gears journaled thereon the desired distance from the shaft 12 comprises a pair of screws 54 and 56 extending into the side edge of the plate 20 and engaging the respective tapered ends of the pin 50. Referring to Figs. 2, 4 and 5, it will be noted that, since the shaft 38 is eccentrically located with respect to the axis of the disc 48 and is fixed to the disc 43, the retraction of the screw '56 and the advance of the screw 54 will move the shaft 33 closer to the shaft 12, thereby moving the intermeshing gears into closer mesh with respect to each other. 7

The adjusting mechanism shown in Figs. 2, 4 and 5 is useful in assembling the gears in the Vernier dial mechanism and for taking the mechanism apart, since the shaft 38 may be readily moved slightly away from the shaft 12 to loosen the gears 36 and 40 with respect to the gears 32 and 44.

The gear 44 with its sleeve or hub 46 has a bearing seat or is journaled on the shaft 12, and the hub 26 attached to the hub or sleeve 46 have a bearing seat endwise with respect to the dial 16 so that the peripheral portion of the hub 26 and the disc section 28 of the dial 22 rotate free of the dial 16. The carriage around the shaft 12 is provided with a thrust bearing 58 engaged by a thrust sleeve 60 extending through the support plate around the shaft 12 and bearing against the gear In this construction the arrangement is such that the back edge of the cylindrical flange of the vernier dial rotates just free of the supporting plate 20. I

Fig. 3 illustrates the relationship of the dials "16 and 22 and the support plate 20. The scale '18 of the dial 16 is provided with the usual numbered closely spaced thousands graduations, while the dial 22 is provided with widely spaced unnumbered graduations each representing one thousandth of an inch. The scales of both of these dials are readily referred to with respect to the fixed zero index 62 on the fixed support plate 20 adjacent to the scale of the dial 22. However, the fixed plate 20 also advantageously carries an index plate 64 provided with a second zero index indicator 66 which spans the dial 22 'toa position adjacent to the edge of the scale 18. The index plate 64 is preferably provided with indices 68, 70 and 72 for respectively determining or measuring one fourth, one-ha1f and three-fourths of a graduation or space on the Vernier dial.

In the operation of the veruier dial mechanism, the operator can readily read the heavy numbered lines for the scale 18 which are five graduations apart and by operating the handle 14 very slowly and watching the vernier dial 22, he can adjust the setting to a desired fraction of a thousandth, as for example, by estimating one-fourth, one-half or three-fourths, without any 'difliculty or eyes'train. If the cross slide or other part of a production machine is to be adjusted a certain amount, as for example 17 /2 thousandths, the operator can readily observe the movement "of the scale 18 through fifteen thousandths, then watch the movement of the scale 22 through two thousandths, and finally move the dial 22 until the graduation line to the left or below the index 76 is in register with the index 70, to add the one-half thousandth. One-fourth or three-fourths of a thousandth is measured in the same way by using the indices 68 and 72, respectively. The indices 68, and 72 make it unnecessary for the operator to estimate the fractions.

While the Vernier dial 22 is illustrated as being divided into relatively wide graduations, each equal to one thousandth of an inch, it is possible to mark these graduations into halves and fourths, but it is preferred to use the indices 68, 7t) and 72, or no mark at all for these intermediate graduations, since the operator can readily estimate one-fourth, one-half or three-fourths of the relatively wide spaces of the dial 22. The markings on the dial 22 correspond to the closely spaced graduations of the dial 16, so that when a five division line of the scale 18 is at the position of the index 66, one of the scale lines of the dial 22 will always be at the position of the zero index 62.

The primary and useful purpose of the dial arrangement of the present invention is to provide means including the vernier dial for increasing the distance between the graduations, or provide a dial having widely spaced graduations so as to simplify the determination of fractional movements of the tool and for holding close tolerances. In one method of using the mechanism, the regular dial 16 is marked with a clip on setting up a job on the machine. This setting of the clip is used for a given tool to cut a certain diameter or amount of the workpiece. The vernier dial is then consulted and used to determine how much of a graduation before or past the clip one must go to hold a certain diameter. The greater the spacing of the graduations on the vernier dial 22 the easier it is to determine a portion of the distance from one graduation mark to another. The movement of the vernier dial is much greater than that of the regular dial in taking a like amount of material off the diameter of the workpiece and thereby makes it easier for the machine operator, who is thereby able to produce much more accurate work, and without eyestra-in, or the use of a magnifying glass, which is sometimes used by operators of standard dial arrangements.

From the foregoing description it will be apparent that certain modifications may be made without departing from the spirit and scope of the invention. For example, the spaces between the scale markings on the dial 22 may be made convenient and useful distances apart by selecting the gear ratios used for driving the vernier dial 22. Furthermore, while the means shown for rotating the adjustin'g disc 48 is simple and effective as well as inexpensive to manufacture, other means may be utilized, and in any case such means may be mounted in or on the carriage instead of using the plate 2%. The screws 54 and 56 provide a concealed means which can be tightened and which will not come loose by accident. Furthermore, the entire arrangement for adjusting the meshing force applied to the gears for driving the Vernier dial is free front I any play. This mechanism provides a means by which the dial arrangement may be periodically checked and the gears tightened periodically to insure accuracy and dependability.

What I claim is:

1. In a dial indicating mechanism for production machines including a mounting, a feed screw shaft rotatably arranged in said mounting against axial movement for actuating the tool of a production machine, a handle on the end of said shaft for effecting its rotation and an indicating dial fixed to said shaft inwardly of the handle, the improvement comprising a vernier dial journaled on said shaft inwardly of and adjacent said indicating dial, a forwardly projecting shaft back of the vernier dial parallel to the feed screw shaft, gear means journaled on said projecting shaft, a gear fixed to the feed screw shaft meshing with said gear means, a gear fixed to and located axially of the vernier dial and meshing with said gear means, said gear means and gears being proportioned to drive the vernier dial at a substantially faster rate than the indicating dial is driven when the feed screw shaft is rotated by the handle, a graduated scale on the indicating dial including closely spaced graduations each representing a unit of measurement, and a graduated scale on the vernier dial having widely spaced graduations each equal to one of the closely spaced graduations of the indicating dial, whereby said graduations on the vernier dial are readily visible to and readily proportioned by the operator.

2. A dial indicating mechanism as claimed in claim 1, including means for moving said projecting shaft bodily toward and away from the feed screw shaft for adjusting the meshing of the gear means with the gears, whereby said gear means and gears are maintained in accurate mesh and any wear in the gears may be readily compensated for to maintain the accuracy of the vernier dial.

3. A dial indicating mechanism as claimed in claim 2, in which the means for moving the projecting shaft includes a rotatable disc mounted in a circular fitting recess in a fixed part of the mechanism in spaced relation to the axis of the feed screw shaft, said projecting shaft being mounted eccentrically with respect to said disc, and means for rotating said disc on its axis to thereby move the projecting shaft toward and away from the feed screw shaft.

4. A dial indicating mechanism as claimed in claim 3, in which the means for rotating said disc includes a pin through the disc extending generally diametrically with respect thereto, and means for acting on the pin for effecting rotation of the disc.

5. A dial indicating mechanism as claimed in claim 4, in which a pair of spaced set screws extend into said fixed part of the mechanism, said screws respectively engaging the same side of said pin adjacent its respective ends.

6. A dial indicating mechanism as claimed in claim 1, in which said gear means includes a gear of relatively small diameter meshing with the gear fixed to the feed screw shaft and a gear of relatively large diameter fixed axially with respect to the gear on said projecting shaft and meshing with the gear fixed to the vernier dial.

7. A dial indicating mechanism as claimed in claim 6, in which the gear of relatively small diameter mounted on said projecting shaft includes a projecting hub por tion to which said gear of relatively large diameter is fixed.

8. A dial indicating mechanism as claimed in claim 1, in which the gear fixed to the vernier dial includes a hub portion projecting therefrom extending forwardly along the feed screw shaft, and the vernier dial includes a hub portion surrounding and fixed to said forwardly projecting hub portion.

9. A dial indicating mechanism as claimed in claim 1, in which the vernier dial includes a disc section extending radially with respect to the iced screw shaft, and a rearwardly extending cylindrical peripheral portion overlying said gear means and gears.

10. In a dial indicating mechanism for production machines including a mounting, a feed screw shaft rotatably arranged in said mounting against axial movement for actuating the tool of a production machine, a handle on the end of said shaft for effecting its rotation, and an indicating dial fixed to said shaft between the handle and the mounting, the improvment comprising a vernier dial journaled on said shaft between the mounting and said indicating dial, a fixed supporting plate between the vernier dial and the mounting, a forwardly projecting shaft carried by said plate parallel to the feed screw shaft, small and large connected gears journaled on said projecting shaft, a large gear fixed to the feed screw shaft meshing With said small gear, a small gear fixed to and located axially of the vernier dial and meshing with said large gear on the projecting shaft, said large and small gears being proportioned and arranged to drive the vernier dial at a substantially faster rate than the indicating dial is driven when the feed screw shaft is rotated by the handle, a graduated scale on the indicating dial including closely spaced graduations each representing a unit of measurement, and a graduated scale on the vernier dial having widely spaced graduations each equal to one of the closely spaced graduations of the indicating dial, whereby said graduations on the vernier dial are readily visible to and readily proportioned by the operator.

11. A dial indicating mechanism as claimed in claim 10, including means carried by said supporting plate for moving said projecting shaft bodily toward and away from the feed screw shaft for adjusting the meshing force applied by the gears journaled on the projecting shaft to the gears with which they mesh, whereby said gears are maintained in firm meshing engagement and any play avoided.

12. A dial indicating mechanism as claimed in claim 11, in which the means for moving the projecting shaft includes a rotatable disc mounted in a circular fitting recess in the supporting plate in spaced relation to the axis of the feed screw shaft, said projecting shaft being carried eccentrically by said disc, and means for rotating said disc on its axis to thereby move the projecting shaft toward and away from the feed screw shaft.

13. A dial indicating mechanism as claimed in claim 10, including a Zero index and a series of spaced indices spaced from the Zero index respectively representing different fractions of a graduation of the vernier dial, said series of indices being located at predetermined positions with respect to graduation marks on the vernier dial when one of said graduation marks is in register with the zero index.

14. A dial-indicating mechanism as claimed in claim 1, including a fixed Zero index and a series of spaced indices spaced from the Zero index respectively representing different fractions of a graduation of the vernier dial, said series of indices being located at predetermined positions with respect to graduation marks on the vernier dial when one of said graduation marks is in register with the zero index.

References Cited in the file of this patent UNITED STATES PATENTS 1,760,938 Edgar June 3, 1930 2,319,480 Saving May 18, 1943 2,492,545 Watcher Dec. 27, 1949 

